The invention relates to a shackle lock, particularly with a long shackle, comprising a lock body, a lock shackle with two shackle arms the free end portions of which are displaceable into a shackle arm housing of the lock body until they reach a locking position of the lock shackle, a lock mechanism rotatable about an axis of rotation, particularly by means of a key and, disposed in the lock body at least one locking element which meshes with the closure mechanism and which, upon actuation of the closure mechanism, is guided for movement out of a lock shackle arresting position in which the locking element is in engagement with the end portion of at least one shackle arm for locking the lock shackle and into a lock shackle releasing position in which the locking element is out of arresting engagement with the end portion of the shackle arm so that the shackle arm can be withdrawn completely from the shackle arm housing.